Yes and no. The powertrain is big and expensive, but it's a fairly small fraction of the car's complexity. (And some parts of the cabin climate system are probably also high-voltage for power and packaging reasons, but that doesn't change the discussion here.)
But everything else, the instruments, the infotainment and telematics, the ADAS, the windows and wipers and headlights, seats and airbags and lock solenoids, the list goes on... That represents a lot of complexity and cost, a lot of moving parts, and it's all still 12-volt. Partly for legacy reasons, partly for safety. (There was a push 20 years ago to go 42 or 48 volts to make the wire thinner while still being LV/SELV safety, but legacy held it back.)
Plus all the undercar stuff, wheels and bearings and control arms and bushings, half-shafts and CV joints and boots and swaybars, wheels and tires and stuff, that just never changes, and since EVs tend to be heavier, they tend to be harder on all that stuff than their ICE counterparts.
So there's plenty of stuff you can service with good old mechanic skills and tools, and plenty of it needs servicing.
Well, I think the idea is that while it would be difficult to work on an EV motor yourself, it's also much less necessary, as electric motors are much simpler, with far fewer moving parts. I don't know if we have enough data yet to evaluate, but EV's should be much lower maintenance in that regard.
Outside of the powertrain, seems like the rest of the car should be similar though, like tires and brakes, right?
I always thought of the volt as twice the complexity, twice the responsibility.
You still have to keep track and change the oil, and the coolant. You still have a water pump and spark plugs and all this other stuff to keep track of.
At 48 volts you start running engine accessories off of the electrical bus instead of belts and pulleys. That means the engine isn't necessarily responsible for keeping everything under the hood running at all times. You might not need a water pump or the AC when the engine is off, except to keep the cabin comfortable. But you still need things like power steering and power brakes, stability control and other safety systems.
Also, you start getting economies of scale with all-electric car components that pull down the price of EVs over time, because they can use the same components.
Definitely, I saw this from working on hybrids when I was a mechanic. The transmissions were simpler, the engine rarely needed any work since they ran less than a gas only car. They barely needed any brake work since the electric motor does most of the stopping.
A full electric pretty much eliminates all the work besides replacing tires and replacing the brakes maybe once in the car's lifetime.
Some customers with older evs will need new batteries but the price of a battery is so expensive that dealers won't have a lot of room for markup and it only takes a few hours to replace one.
Yeah, but electric cars have so many fewer moving parts that they just don’t need much maintenance at all. As someone who has an EV now, I’m never going back because EVs are just so much better overall.
Why would a car need a 48V system for accessories? In general the things a car's 12V system powers have gotten less power hungry over time (LED's, heat pump) and in particular, an EV loses the highest power electrical device on the 12V bus, the starter. The typical equipment used for the entertainment and control systems are going to be much more available with 12V supplies, just because that's the industry standard.
Obviously the traction system is using much, much higher voltages.
The article cites "complexity" of the wiring harnesses, which is nonsense. The wires might get a little smaller, but not by a lot. Like I said, the 12V bus in an EV isn't driving a bunch of high power stuff. (Is it? Am I missing something?)
The one place I can imagine it helping is for driving inverters so you can provide AC outlets for laptops, power tools, etc.
it is ironic that while mechanically EVs are much simpler, they are only shipped with all the complexity from electronic side.
i am not an automobile engg, but the core parts required to run an EV (motor control, battery management, etc.) has to be comparable to the ECU that are in decades-old Hondas and Toyotas.
I don't know enough about all the parts of the car, but generally speaking, many people have argued that an electric car is much simpler than a mechanical car. (Something to do with the complexity of the engine, gear, drive train etc).
If I recall, one study indicated that maintenance costs on an ev are a fraction of the current costs for that reason.
Power steering pumps are electric and have one of the largest wires in my truck. With an EV you also have a heat pump, maybe a heater, coolant pumps now that you don't a constant spinning pulley, windows, lights, headlamps, power doors, seats, radio, amplifier, small PC, etc.
From the article
"Switching to 48V architecture alleviates a huge number of challenges automakers are facing with 12V. The biggest one, though, is complexity: You need far less complex wiring harnesses to power all your vehicle systems"
My take is that 12v requires almost a dedicated power line for each part, while a 48v could run to a bus line that gets tapped. 48v might be something that divides easier with the battery pack, and drops the 12v battery.
Whoever is saying electric vehicles has reduced complexity has no idea what they are taking about. Literally none. It’s complete fantasy.
The THEORY you could make an EV less complex is probably true, but the REALITY is not.
There isn’t a single EV in the world today that is less complex than it’s non-EV relative.
Chrysler and GM EV and HEV specially I’ve worked on both have entirely separate bus systems just for the power train, this is on top of the already existing PT bus that the ICE vehicles all have. The battery heater, the battery pump/cooler, the multiple charging systems, the additions to the transmissions systems, the ABS systems in ICE that handle stability control were already complex, now more so because they are entirely new devices that bring in regenerative braking and efficiency. All the software has changed around target torques/rpm/target gear for mileage. There is no other brand that defies my assertion.
Literally everything in an EV is more complex. Didn’t have to be, but is.
> I would presume electric drive trains are quite complex.
They're significantly less complicated than an ICE power-train and drive-train.
The Nissan Leaf has a single electric motor and a fixed reduction gear box. The only fluids to maintain are the wiper fluid and reduction gear box fluid, which is similar to automatic transmission fluid but requires less maintenance. The battery pack is air cooled and the only servicing is an annual inspection to maintain warranty.
The Tesla vehicles are all direct drive with no gearbox. They come in single or dual motor options. The batteries are cooled and the fluid is changed at 4 year intervals.
The maintenance schedule for an EV is annually changing the cabin filter, wiper blades, and doing a multi-point inspection.
Electric cars don't have engines or transmissions. But lately I have not found that that is where problems occur. They still have all the other things that ordinary cars have such as tires, brakes, wheel bearings, suspension parts including shocks, springs, struts, sway bars, bushings and links, steering mechanisms, electronic control systems both for the motor and the interior accessories, all kinds of small things like power windows, power seats, lights, entertainment and navigation, many of which need periodic replacement if not routine maintenance, and all of which may fail unexpectedly and require repair.
For an EV car, the vast majority of work needed has no relation to the drivetrain (which is relatively low-maintenance on an EV), so it doesn't really matter if half of mechanics don't know how to work on EVs; fixing suspension or doing bodywork doesn't change.
In general fully electric vehicles are much simpler mechanically and need vastly less servicing. The bit of scheduled maintenance that they do need to be handled by anybody.
So the electric car doesn't have an interior that will be worn out? Or worn suspension components like ball joints, tie rods, bushings, steering rack? Or air conditioning?
Electric cars also have highly sophisticated power control equipment. In 10 years of sysadmin work, the overwhelmingly most common failures I've seen have been power supplies, voltage regulators, and capacitors. Remains to be seen how well these components will hold up in real-world use in electric cars.
I think it is a fallacy that EVs are simpler. You have just moved mechanical regulators to software so the complexity is hidden. I.e. instead of a timing belt you have an inverter etc. Instead of a water pump driven by a belt you habe an electrical pump cooling the batteries and motor.
But everything else, the instruments, the infotainment and telematics, the ADAS, the windows and wipers and headlights, seats and airbags and lock solenoids, the list goes on... That represents a lot of complexity and cost, a lot of moving parts, and it's all still 12-volt. Partly for legacy reasons, partly for safety. (There was a push 20 years ago to go 42 or 48 volts to make the wire thinner while still being LV/SELV safety, but legacy held it back.)
Plus all the undercar stuff, wheels and bearings and control arms and bushings, half-shafts and CV joints and boots and swaybars, wheels and tires and stuff, that just never changes, and since EVs tend to be heavier, they tend to be harder on all that stuff than their ICE counterparts.
So there's plenty of stuff you can service with good old mechanic skills and tools, and plenty of it needs servicing.
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